Different quantities and quality of fat in milk products given to young children: effects on long chain polyunsaturated fatty acids and trans fatty acids in plasma.

UNLABELLED: In this study we compared plasma contents of long-chain polyunsaturated fatty acids (LC-PUFAs) and trans fatty acids in triglycerides (TG), phospholipids (PL) and cholesterolesters (CE) in young children fed milk diets containing different amounts of linoleic (LA) and alpha-linolenic acid (ALA). Because the diets differed in vitamin A and E content, plasma concentrations of vitamin A and E were also studied. Thirty-seven 1-y-old children were randomly assigned to one of four feeding groups: (1) low-fat milk (LF) (1.0 g cow's milk fat/dL); (2) standard-fat milk (SF) (3.5 g cow's milk fat/dL); (3) partially vegetable fat milk (PVF) (3.5 g fat/dL; 50% vegetable fat from rapeseed oil, 50% milk fat); and (4) full vegetable fat milk (FVF) (3.5 g fat/dL; 100% vegetable fat from palm-, coconut- and soybean oil). We found higher amounts of plasma LA in the FVF group than in the LF and SF groups (p < 0.001) and higher amounts of ALA in the PVF group than in the SF (p < 0.001 in TGs, p < 0.05 in CEs) and LF (p < 0.01 in PLs and CEs, p < 0.05 in TGs) groups. However, amounts of plasma arachidonic acid (AA) were similar between groups as well as the amounts of docosahexaenoic acid (DHA) in CEs and PLs. Total trans FAs were lower in CEs in the PVF and FVF groups than in the SF group (p < 0.05 SF vs PVF; p < 0.01 SF vs FVF). Plasma concentrations of alpha-tocopherol were higher in the FVF group than in the other groups (p < 0.05 FVF vs SF, p < 0.01 FVF vs SF and PVF). CONCLUSION: Children consuming milk diets containing high amounts of vegetable fat present with higher plasma LA and ALA without any effects on amounts of plasma LC-PUFA. The plasma LC-PUFA status is not adversely affected by a low-fat milk diet. AHA and DHA in plasma are not affected by the diets studied, presumably because 15-mo-old children may be able to compensate for dietary influences through endogenous LC-PUFA metabolism.

Fatty acid content of plasma lipid fractions, blood lipids, and apolipoproteins in children fed milk products containing different quantity and quality of fat.

BACKGROUND: Differences in fatty acid content of plasma lipid fractions and serum lipid concentrations were investigated among young children fed different milk diets composed to achieve a recommended saturated fat intake. METHODS: Thirty-eight healthy children were randomly assigned to one of four feeding groups at 12 months: 1) low-fat milk (1.0 g/dL cow's milk fat); 2) standard-fat milk (3.5 g/dL cow's milk fat); 3) partially vegetable fat milk (3.5 gtat/dL fat; 50% vegetable fat: rapeseed oil); and 4) full vegetable-fat milk (3.5 gtat/dL fat; 100% vegetable fat: palm, coconut, and soy oil). Plasma fatty acids, blood lipids, and apolipoproteins were analyzed at 15 months, and dietary intakes at 12, 15, and 18 months. RESULTS: There were significantly lower percentage contributions of saturated fatty acids in plasma triglycerides in children fed low-fat milk or milk with 50% or 100% vegetable fat than in children fed standard-fat milk. Plasma polyunsaturated fatty acid levels were significantly higher in children fed milks with vegetable fat than in children fed standard-fat milk. Plasma saturated and polyunsaturated fatty acids in triglycerides most closely reflected dietary intake. Blood lipid concentrations were lower in children fed milk with 50% vegetable fat. CONCLUSIONS: Children fed milk with 50% or 100% vegetable fat, together with high vegetable-fat and low milk-fat dairy products have lower percentages of plasma saturated fatty acids and higher percentages of polyunsaturated fatty acids than children fed standard- or low-fat milk and dairy products.

Macronutrient and energy intakes in young children fed milk products containing different quantities and qualities of fat and protein.

BACKGROUND: Milk is the major source of protein and saturated fats in the diet after infancy. In the present study, the effects of different fat and protein quantity as well as fat quality in milk and dairy products on nutrient intake and growth in young children were determined. METHODS: Thirty-eight healthy children were randomly assigned to one of four feeding groups at 12 months of age: 1) Low-fat milk (1.0 g fat/dl, 3.3 g protein/dl); 2) standard-fat milk (3.5 g fat/dl, 3.3 g protein/dl); 3) partially vegetable fat and protein-reduced milk (3.5 g fat/dl, 50% vegetable; 2.2 g protein/dl); and 4) full-vegetable-fat milk (3.5 g fat/dl, 100% vegetable; 3.0 g protein/dl). Nutrient intake and growth were measured at 12, 15, and 18 months. RESULTS: The protein intake was significantly reduced with the protein-reduced milks. The intake of saturated fat was significantly lower with low-fat milk (11% of energy) or milks containing vegetable fat (13%) than in standard-fat milk (19.6%). However, the total fat intake was below 30% of energy in low-fat milk, whereas the total fat intake remained more than 30% in the other groups. Energy intake and growth were similar in all groups. CONCLUSIONS: A modified milk with reduced protein content for young children results in protein intakes closer to recommendations. A modified milk with either 50% or 100% vegetable fat and dairy products with low milk fat and high vegetable fat content results in intakes of total and saturated fats closer to international recommendations, compared with standard or low-fat milk and dairy products.

Higher concentrations of serum transferrin receptor in children than in adults.

BACKGROUND: The serum transferrin receptor (TfR) concentration in adults is suggested to provide a sensitive measure of iron depletion and together with the serum ferritin concentration to indicate the entire range of iron status, from iron deficiency to iron overload. However, little is known about TfR concentrations in children. OBJECTIVE: Our objective was to compare serum TfR and ferritin concentrations and their ratios in children and adults and look for correlations between TfR concentrations and other measures of iron status. DESIGN: Our study groups were healthy 1-y-old infants (n = 36), 11-12-y-old prepubertal boys (n = 35), and 20-39-y-old men (n = 40). RESULTS: TfR concentrations were higher in infants (x; 95% reference interval: 7.8 mg/L; 4.5, 11.1) than in prepubertal boys (7.0 mg/L; 4.7, 9.2) and higher in prepubertal boys than in men (5.8 mg/L; 3.1, 8.5). Geometric mean TfR-ferritin ratios were higher in infants (316; 95% reference interval: 94, 1059) than in prepubertal boys (219; 78, 614) and higher in prepubertal boys than in men (72; 23, 223). By multiple linear regression analysis, the best predictors of TfR concentration were serum iron (P = 0.004) and log serum ferritin (P < 0.0001), both being inverse correlations (R2 = 0.32). Mean corpuscular volume, blood hemoglobin, transferrin iron saturation, transferrin, and even age seemed to not have an influence on the TfR concentration and erythropoiesis was not a determinant of TfR concentration. CONCLUSIONS: Low serum ferritin and iron concentrations, even within the normal physiologic range, result in high TfR concentrations. The lower the iron stores, the stronger the influence of ferritin on TfR. A high TfR concentration in children, especially in infants, is a response to physiologically low iron stores. Age-specific reference concentrations for TfR are needed.